1456 rounded to the nearest hundreds is 1500. When rounding to the nearest hundred, you look at the digit in the tens place. If it is 5 or greater, you round up; if it is less than 5, you round down. In this case, since the digit in the tens place is 5, you round up the hundreds place to 5 and the rest of the digits become 0.
It would round to 1500
80,000 is already rounded to the nearest hundreds.
500
0
0
3571000
2600
6600
3600
4300
4800
1400